Rotary well drill feed



H. w. THORNBURG 'Y 2,869,826

Jan. 20, 1959 'ROTARY 'wELLjDRILL FEED 7 Sheets-Sheet 1 Filed Aug. 1 4.195s w.'rHomsuR INVENToR.

. ATTORNEY.

Jan. 20, 1959 H. w. THORNBURG v I2,859,826

ROTARY WELL DRILL FEED Filed Aug. 14.l 195s vvsheets-sneet 2 HERBERTW'THORN BURG,

INVENTOR.

Jan. 20, 1959 H. w. THORNBURG ROTARY WELL DRILL FEED 7 Sheets-Sheet 3Filed Aug. 14, 1953 v INVENTOR.`

' ATTORNEY.

Jan. 20, 1959 f H. w. THORNBURG 2,869,826

v l I ROTARY WELL DRILL FEED Filed Aug. 14. 195s l 7 sheets-sheet 4v LIIll 4 Il lig v I+ um a@ HERBERT; W-THom BURG,

mwen/T012.

H. W. THORNBURG ROTARY WELL DRILL FEED Jan. 20, 1959 '7 Sheets-Sheet 5Filed Aug. 14, 1953 IN V EN TOR.

HERBERT W -THORNBURG VIC-:1.1L

ATroR NEK Jan. 20, 1959 H. w. THORNBURG ROTARY WELL DRILL FEED 7Sheets-Sheet 6 Filed Aug. 14, 1955 HERBERT W.THORNBURG1) Arron NEZ Jan.20, 1959 H. w. THoRNBuRG 2,869,826

ROTARY WELL DRILL FEED v Filed Aug. 14, 195s "rsheetS-sheet 7 l MoToRPeD Moron PULL.

AMPERES FE1; I7

HERBERT N THoRNBoRa,

` JNVENToR.

AT1-ORNE! i 3 O D ROTARY WELL DRILL FEED Herbert W. Thornburg, SouthMilwaukee, Wis., assigner to Bucyrus-Erie Company, South Milwaukee,Wis., a corporation of Delaware Application August 14, 19s3,seria1 No.374,364

s claims. (Cl. ass- 22) This invention relates to well-drillingequipment, andv ing the effect on motor pull (or holdback) of anincrease 2) The downward force on the drill string is imposed by meanshaving selectively either a high or a low forcespeed ratio.

(3) The rotary drive power means for the drill string travels with andadds its weight to the drill-string.

(4) A uniform cut is achieved by the drill bit without back-up orbouncing of the tool. k

vIn addition to the principal objects, above stated, a number of noveland useful details have been worked out which will be readily evident asthe description progresses.l

The invention consists in the novel parts and in the combination andarrangement thereof, which are defined in the appended claims, and ofwhich -one embodiment is exemplified in the accompanying drawings, whichare hereinafter particularly described and explained.

Figure 1 is a side elevation ofa rotary blast-hole drill embodying theinvention.

Figure 2 is an enlarged horizontal section taken along the line 2-2 of`Figure 1, showing the lower'main frame and main machinery of the drill.

Figure 3 is a partial schematic end View of the derrick vshowing thehoist and pull-down reeving for raising and lowering the rotary driveunit on the derrick.

Figure 4 is a side elevation taken along the line 4-4 of Figure 3. K

Figure 5 is an enlarged side elevation ofthe derrick and the derrickhoist reeving, with the derrick in horizontal travelling position. Y I

' Figure 6 is an end view of the derrick and the derrick hoist reeving,taken along the line A6--6 of Figure 5.

Figure 7 is an'enlarged end view ofthe verticaltraverse l frame and therotary driving unit. I' Figure 8 is a horizontal section,taken'alongthe-line S-Sof Figure 7, showing the gear and rack connectionbetween the yvertical traverse frame and the derrick.

Figure 9 is a horizontal section, 'taken along the line 9-9 of Figure 7,showing the sliding connection between the lower end of the verticaltraverse frame and the derrick.- Y

Figure 10 is a vertical section, taken along the line 10Q-10 of Figure7, showing the brake mechanism of the A.

shipper-shaft drum in set position. n n v v `Figure l1 is a Verticalsection, similarto Figurel 10,

showing said brake mechanism in unset position.-

'A Figure 12 is an enlarged plan View, partially in. section,

showing the main'machinery for tool pulldown,derrick hoist,and propel. g

YFigure 13 is avertical section, taken alongthe. line 'i 13,-13 ofFigure 12, lshowing the 'uid pull-down motor and reductionfdrivemechanism."

2,869,826 Patented Jan. 20, 1959 "ice in reverse speed of the motor whenthe drill tool strikes soft digging. y

Turning now to Figures 1 and 2, it is seen that the rotary blast-holedrilling apparatus that is the illustrative embodiment of the invention,comprises `a horizontal mobile base 11, preferably mounted on crawlers12 and three hydraulic levelling jacks 13, which supports a derrick 14,tool-handling unit 15, air-compressors 16, compressor motors 17, motorgenerator set 18 and the main machinery (hereinafter described) forhoisting the derrick, raising and lowering the drill string togetherwith its rotary-drive mechanism, handling drill pipe, and propelling themachine. The drill string 34 includes at its lower end a rotary drillbit 34a.

Derrick 14 is a one-piece unit that is pivotally mounted at 19 onA-frame 20 on base 11, so that it can be lowered from its normalvertical operating position to a horizontal travelling position (shownby broken lines in Figure l). The derrickis raised and lowered by meansof hoist cable 21 which runs (see Figures 5 and 6) from power-drivenderrick hoist drum 22 on base 11 to and' about guide sheaves 23 and 24on base 11,1thence about sheaves 25 and 26 located adjacent the lowerend of the derrick and thence about guide sheave 27v toa dead-end 28 onbase 1'1.

Vertical gear racks 29 rigidly mounted on the derrick provide tracks forvertical traverse frame 30 (see Figures 7 and 9) on which is mounted therotary-drive unit for the drill-tool string. This rotary-drive unitconsists of a generator fed controlled D. C. electric motor 31, anenclosed gear-'case 32 containing gearing (hereinafter described) toconnect the motor-drive shaft to the drive coupling 33 at the top of thedrill-string 34. Horizontal shipper-shaft 35, rotatably mounted at theupper end of frame 30, is keyed to pinions 36, which engage the gearracks 29 on the derrick, and is connected to the shippershaft drum 37through an automatic-brake mechanism (hereinafter described). Thevertical traverse frame' 30 and the rotary driveand shipper-shaftmachinery is raised and lowered on racks 29 by means of hoist cable 38and Vvertical `traverse frame 30 down, and rotating the bull-reel 'drum42 in the opposite direction (counterclockwise in Figuresl and 4) raisesthe vertical traverse frame S0-and hoists the drill string 34. Thereeving and detailedoperation of the hoist and pull-down cables andrtheirassociated apparatus will be described hereinafter in furtherdetail.

Turning now more particularly to Figures 1, 2 and l2-14, it is seen thatthe main machinery on vbase 11 'isV driven bymain hoist and propel motor43 which has a generatorfed control 'and is supplied with power andcontrolled by motor generator setflS. The4 drive shaft of motor 43l isconnected by flexible coupling 37 to one end of the main drive shaft 45to which is splined propel Pinie#- ,46 which att-th, with Papel gear ,47.keyed .te thi@ keyed to its gear 51, turns'to hoist or lower the frame33..

The bull-reel drum 42 may also be driven to pull down frame 34) lby theAfollowing described alternative mechanism. Fluid motor 54 drivespull-down gear 57 rotatably mounted on the end ofbull-reel pinion shaft49,. preferably through double-gear reduction gears 58a, SSb, and`58c(Figures l2 and 13). A second jaw-c iutch 59' connects Ygear 57 topinion shaft 49 so that when the: iluid motor 54 is actuated to turn andjaw-clutch 59 isv engaged and jaw-clutch 53 is vdisengaged,'the fluidmotor 54 will drive thebullreel drum y42, through pinion 53 andvbull-reel gear 51.

Thus the bull-reel drum 42 may at will be driven alternatively at slowspeed with high torque bythe fluid motor 54 which has a relatively-highforce-speed ratio or at higher speed with low torque by the electricmotor 43 whichhas a relatively-low force-speed ratio.

At the end of bull-reel drum 42 adjacent propel gear 47, is'rigidlymounted bull-reel brake housing 6i? for an external contracting-typebrake band 61 for the drum. This brake is mechanically Vcontrolled byconventional means not shown. Therefore, either the brake 66-61 or theelectric motor 43 can be used to brake the lowering of the drill tools.f

An auxiliary-reel drum 62 is also mounted for rotation on and aboutpropelshaft 48. This auxiliary-reel drum 62 fis located adjacent propelgear 47, is drivably connected to drive shaft 4S -by means of jawclutch63, and is braked by a conventional band-type brake 64. This auxiliarydrum is used for erecting machinery, handling pipe, braking bit joints,`and numerous other jobs.

The jaw-clutch 63 that engages the auxiliary drum 62 vis also used toengage vderrick-hcist sprocket 65 to the driveshaft 48. Sprocket 65 isdrivably connected by chain 66 to sprocket 67 that is integral withworm-gear 68 that drives gear 69 on derrick-hoist drum 22. Therefore,when the motor 43 turns the drum-shaft 48 and clutch 63 is engaged withsprocket 65, the derrick-hoist drum 22 will turn to raise or lower thederrick.

At each end of the propel and bull-reel shaft 48, there is anair-operated clutch 71 with attached pinion 72 that rotates aboutt-heaxis of the drumshaft. .A conventional outside band-type brake 73,also air-operated, engages the periphery Vof the housing of each clutch71. Each pinion 72 drives a propel gear 74 located integral withsprocket 76 (Figure 1). Propel chain 77 drivably connects sprocket 76 tothe tumbler-drive sprocket 73 of the adjacent crawlerV 12 (see Figure1). Thus itis seen that each .crawler is individually driven and steeredby its adjacent' clutch and brake 71 and 73 respectively.

Turning now to Figures 3 and 4, the bull-reel drum 42 and theshipper-shaft drum 37 are drivably connected with vertical traverseframe 30 by the following-described reeving to hoist and pull down thevertical traverse frame 30 on derrick 14. Two cables 38 and 39.are usedin this reeving scheme, one cable 38 for hoisting and the other cable 39for pull-down. With the shipper-shaft drum 37 in lowered position, asshown in Figures 3 and 4, the hoist cable 38 is anchored at one end 80of the bull-reel drum 42 and one-half Wrap is put around the drum. Thecable 38 is then reeved over the upper eeting sheave f4'0lo'cated at thetop -of the der'ri'ck and then brought down to the' shipper-shaft drum37in its lowered position. 'An appropriate number of wraps (suicient tohoist the frame `30 `to the Vtop ,of the derr'ick) are then put on the"shippershaft drum 37 and the cable 38 is then anchored Cil at the endS1 on the drum l37. The pull-down cable 39 is anchored at 82 on theopposite end of the shipper-Shaft -drum 37 and one wrap is put aroundthe drum in the lopposite direction to the hoist cable 38. The pull-downlcable 39 is then brought down around the lower ileeting sheave 41 atthe base ot' the derrick and reeved around the bull-reel drum 42 in theopposite direction to the hoist cable 38. An appropriate number of wrapsof cable 39 (suicient to permithoisting frame 39 to the top of thevderrick) are put on the bull-reelA drum 42 and the pulldown cable 33 isthen anchored at 83 on the opposite end of drum 42. Thereforeyas thebull-reel drum 42 turns in one direction, the shipper-shaft drum 37 andframe 30 is raised, and as it turns in the opposite direction V'theshipper-shaft drum 37 and frame 26 is pulled down.

The above-described hoist and pull-down reeving pro- 'Vides a positiveand continuous downward pull as well as Vupward hoist on the drillstring34 (shown in Figure l). Furthermore, since the horizontal axis ofthe shipper-shaft drum 37 lies vinthe same vertical plane `as thedrill-tool `stern, the pull-'down is applied centrally to the drillstring,

thereby avoiding the excessive strains that would result .from aneccentric pull-down.

Turning now to Figures 7 to 9, it is seen that not only .ftheshipper-shaft drum 37, but also the rotary drive electric .motor 31 'andthe rotaryadriveunit that-connects the .motor to and drives the drillstring, are mounted in vertical traverse frame 30 that runs on gearracks 29 and travels with the drill string. Thus it is seen that a largemass, iinthe form of the lframe 3b and the heavy equipment V'mounted onit, is added to the mass of the drill string and is available'toreact'against and prevent tendency r of the drill bit to back-up orbounce, without cutting, .in the hole as 'the bit rotates. Suchbacking-up or bouncing is to be avoided not only because the bit doesnot c'ut or at best-cutsrunevenly whenit is backing up,

Vbut also because bouncing up and down of the drill string drillstring34 through frame 3G.

Turning now to Figures 10 and l1, as well as to 7, it :is seen thatanother device for preventing bouncing of the drill bit is thefollowing-described automatic brake on the shipper-shaft drum 37. Drum37 is rotatably mounted on shipper-shaft 35, but free rotationof shaft35 is limited by the amount that the head 84 of driver 85 can travelabout shaft 35, to which it is keyed, within internal peripheral notch86 on the, housing of drum 37. Even such limited movement is restrictedby internal expanding oneway brake band 87 which is mounted on drum 37and frictionally engages the inner face of brake housing 88 rlgidlymounted by-support89 on frame 30. Brake band 87 1s actuated by arm 90 ofdriver 8S, the outer end of which engages one end 87a of the brake band,and by bell-crank 91 which is pivotally mounted at 92 .on arm 90 ofdriver 85 and engages the other end 87b of the `brake band. -Set screws93 mounted on drum 37 maintain uniform contact of band 87 against brakehousing 88. Arm 94 of bell-crank 91 is ,actuated by drum 37 throughreach-rod 9S which is biasedA by lug 96 on' drumY 37 to release thebrake band when the drum rotates counterclockwise (Figure 11), fasduring hoisting, and to set the brake band when the drum rotatesclockwise (Figure 10),

l as during pull-down.

Turning now to Figures'3 and 10, it is seen that during pulldown ofthe'drill string, with pull-down cable'38 in tension and actuatingdrun137 to ,rotate clockwise, there will not only be positive drivingengagement between th drum 37 and shaft 35 through driver 84, but brakeband 87 will be set due to the fact that the drilling reaction on shaft35 causes arm 90 of driver 85 to set one kend 87a of band 87 and theopposite rotation of drum 37 and its lug 96 causes Vbell-crank 91 to setthe other end 87b of band 87. If the drill bit starts to back-up, suchmovement is resisted not only by the drum 37 and cable 39, but even morepositively by the automatic setting of brake band 87 which in etectlocks the shaft 35 to the derrick 14.

Turning to Figures 3 and 11, it is seen that when the drum is rotatedcounterclockwise, as in hoisting, the brake band 87 is automaticallyreleased due to the relative clockwise movement of driver 85 and its arm90 away from end 87a of the band 87, and to the counterclockwisemovement of arm 90 on drum 37 which rotates bell-crank 91counterclockwise and releases the other end 87h of the brake band. Thisfrees the shaft 35 to rotate on the derrick. Driving engagement betweenshaft 35 and drum 37, necessary to hoist frame 3i), isobtained throughdriver 85 when it makes contact with the opposite end of notch 86 ondrum 37.

Turning now to Figure 7, it is seen that the lower portion of frame 30carries the rotary drive machinery for the drill string and the couplingwhich provides not only a rotary drive connection, but `also asupporting connection, to the drill -string so that the drill string canbe raised and lowered as well as rotated. Reversible electric motor 31is drivably connected, through reduction gears 97a, 97b, and 97C, togear 98 which is splined to shaft 99 of rotary drive unit 32. Thelower'end of shaft 99 is connected'by ileXible drive coupling 33 to theupper end of the drill string. A pressure fluid conduit 100 is connectedto a stuing box 79 on the'top of the gear case of rotary drive unit 32to supply compressed air (or other pressure fluid) from a source to thehollow core of drill string 34.

Turning now to Figures l5 to 17, it is seen that the main hoist motor 43(designated M in Figures 15 and 16) has a generator-fed electric motorcontrol system which consists of a main generator 18 (designated G inFigures and 16) and its associated windings and control. Generator G isexcited by separate eld winding 171 and includes in its secondarycircuit series eld winding 172 and shunt self-field winding 173.'Current from low-voltage D. C. source E to winding 171 is manuallycontrolled by a conventional reversing contro-ller 174, the controlhandle 175 of which vhas a plurality of settings, say four,corresponding to a series of taps off of resistor 176 in the primarycircuit of generator G. These control points are numbered from l to 4 oneach side of neutral (zero pull) and in that order represent points forobtaining progressively greater excitation generator current and,therefore, progressively greater motor speed and pull for both hoisting(positive excitation) and lowering (negative excitation). The motorspeeds obtained for various degrees of motor pull or load are shown inFigure 17 by a family of speed-pull (voltage-ampere) motor characteristccurves, each curve representing one setting of the controller 174.

When the controller is set at position +4 (see Figure l5), in order tohoist the drill string 34 and frame 30, the required motor pull will beequal to say OP in Figure 17 so that the operating point on the +4characteristic curve in Figure 17 will be at point C and motor speedwill equal OR. If now, the drill string is allowed to drop or is movingdownward in digging, the weight of the drill string and rotary drivemachinery on frame 30 will be so great that, even with the controllersetto hoist in position .+1, nevertheless the weight of the drill stringand machinery will overcome the upward motor pull and the motor willrotate in reverse and the drill string will drop, the reverse motorspeed being indicated by OS in Figure 17 and the operating point by A onthe +1 characteristc curve. Then the motor M can be used to hold backthe drill string yduringdigging., lf, during digging a soft spot isreached so that the downward vspeed of the drill string and motorincreases, then the hold-back pull of the motor will `automatically,increase in response to such increase in speed, thenew operating pointbeing say at B on the +1 characteristic curve of Figure 17. r

In Figures 15 and 16 the directions of the flux in thewindings171,'172`a`nd 173y are shownvfor the controller 174 set forpositive hoist, the controller onv the one hand (Figure l5) being set atposition +4 to provide sutilcient excitation current to hoist the drillstring, and on the other hand (Figure 16) at position +1" to hold backthe drill string when it is moving downward under its dead weight. Itwill be noted thatthe effectrofreversingy the direction of movement'ofthe motor M,y without reversing the controller, is to reverse thedirection of the shunt self-field 173, without alecting the direction ofthe series-held 172 or the separate excitation field 171. Accordingly,although the motor is travelling in a reverse direction, namely downwardinstead of upward, a net upward pull of thexnotor is'maintained, theamount of such pull being shown, for a given setting .of the con.-l

troller, by the characteristicY curve in Figure 17.

`The above-described.control-system for the motor M provides a llexiblecontrol'of the-drill string that is not possible with conventionalsystems. Thus, when operating in reasonably-hard material, whichrequires very little pull-down on the drill string, the controller 174can be set at position 1 for pull-down on the drill string just sucientto give the proper drilling speed. In other types of material the.one-point pull-down. is too much and will cause 'the drillingoperationtofrbecome overloaded. `In this case, the controller"174 can beset in neutral position, producing nofpull-down, or,'if overloadingstill continues, the controller; 174 can be set in t+1 hoisting, toproduce ,a low hoisting pull on the ,drillv baclrI orrretard the gravitystring just suiiicient tohold action of the tool load.

If the drilling becomes comparativelyihard, then the vlow-speedhigh-torque iiuid pull-down motor 54 can be used instead of, orin addition to, the electric pull-down motor43 (M). The use of motor 54to add its force to motorA 43 (M) for heavy .pull-down vis referred tohereinafter as operation of said motors in tandem.

Thus it is seen, that the supplementary use of the lowspeedhigh-torquepull-down motor 54 and the electric` pull-down and hoistmotor 43 (M) results in a wide range of control of the drill string fromslightly holding back to a comparatively heavy pull-down.

, Having now described one embodiment of the invention,y it is to beunderstood thatthe invention is not to be limited toI the specific formor arrangement of parts herein described and shown.

I claim:

l. In a rotary well-drilling apparatus the combination of: aground-supported base; a derrick supported by said base; a rotary drillbit adapted to rotate about its vertical axis; a vertical traverseframe; means supporting said vertical traverse frame on said derrick forvertical movement relative thereto; raising and lowering meansoperatively connected to said vertical traverse frame and to saidderrick to raise and lower said frame on said derrick; rotary drivepower means supported by said vertical traverse frame for verticalmovement therewith; means connecting said drill bit to said rotary-drivepower means for rotation and vertical movement therewith; a lirst motor,supported by said base, having a relatively high force-speed ratio; asecond motor, supported by said base, having a relatively lowforce-speed ratio; first drive means, including a clutch, drivablyconnected to the lirst motor and to the raising and lowering means, forpower lowering said vertical traverse frame with relatively great forceand low speed during drilling; second drive means, including a clutch,drivably connected to the second Vrriotor and tothe raising and loweringmeans, for power loweringY and power` raising said vertical traverseframe to arid from its drilling position at relatively high speed; andmeans, including means common to said drive means, interconnecting saidmotors for selective operation of said motors either independently or inltandem to power lower said vertical traverse frame.

2. In a rotary well-drilling apparatus theV combination of: aground-supported base; a derrick supported by said base; a rotary drillbit adapted to rotate about its vertical axis; a vertical traverseframe; means supporting said frame on said derrick forvertical movementrelatively thereto; power means operatively connected to said frame andsaid derrick toY power-raise and powerlower said frame with respect tosaid derrick; rotary drive power means supported by said frame forvertical movement therewith; means connecting said drill bit to saidrotary-drive power means for rotation and vertical movement therewith;further characterized by the fact that the means supporting said lframeon said derrick for vertical movement relative thereto `includesia pairof vertical gear racks mounted on said derrick' and a pair ofcooperating pinion gears'L rotatably mounted on said frame; that thefirst-mentioned power means is drivably connected to said pinion gearsby double-acting drive means; and that the drive means includes a firstdrum mounted onsaid `frame to rotate about a horizontal axisintersecting the vertical axis of the drill bit and the rotary-drivepower means; drive means connecting said first drum to said piniongears; a second drum supported by the base and driven by thefirst-mentioned power means; and a pair of cables each oppositely woundon, and anchored at each end to, said drums andreeved on said derrick torotate said first drum in either direction thereby to power-raise Yorpower-lower said frame on the derrick when said second drum is rotatedrespectively in speed ratio to power-lower said frame, and a secondindependently operable motor having a relatively-low n force-speed ratioto power-lower and power-raise said a bit-raising or bit-loweringdirection by said iirst-mentioned power means. e Y

3. In a rotary well-drilling apparatus the combination of aground-supported base; a derrick supported by said base; a rotary drillbit adapted to rotate about its vertical axis; a vertical traverseframe; means supporting said frame on said derrick for vertical movementrelative thereto; power means operatively connected to said frame and tosaid derrick to power-raise and powerlower said frame with respect tosaid derrick; rotary drive power means supported by said frame forvertical movement therewith; means connecting said drill bit to saidrotary-drive power means for rotation and vertical movement therewith;said first-mentioned power means including a first motor having arelatively-high forceframe; further characterized by `the fact that themeans supporting said frame on said derrick for vertical movementlrelative thereto includes a pair of vertical gear racks mounted onsaid' derrick and a pair of cooperating pinion gears rotatably Ymountedon said frame; that the first-mentioned power means is drivablyconnected to said pinion gears by double-acting drive means; and thatthe derive means includes a first drum mounted on said frame to rotateabout a horizontal axis intersecting the vertical axis of the drill bitand the rotary-drive power means; drive means connecting said first drumto said pinion gears; a second drum supported by the base and driven bythe first-mentioned power means; and a pair of cables eachoppositelywound on, and anchored at each end to, said drums and reevedon said derrick to rotate said first drum in either direction thereby topower-raise or powerlower said frame on the derrick when said seconddrum is rotated respectively in a bit-raising or bit-lowering directionby said first-mentioned power means.

' 4. A rotary well-drilling apparatus according to claim 3, furthercharacterized bythe fact that the drive means includes brake meansoperatively connected' to the vertical traverse frame and to the firstdrum automatically to vset and hold said first drum rigid with respectto said vertical traverse frame when said first drum is actuated bybacking up of the drill bit to rotate to raise said vertical traverseframe. u v

5. A rotary wellxlrilling apparatus according to claim 3,rfurthercharacterized by the` fact that the drive means includes a driver memberoperatively connected to said pinion gears and to said rrst drum toprovide opposite driving connections therebetween at spaced points ofrotation on said irst drum.

References cited in the are f thispam UNITED STATES PATENTS

